Full Spectrum Questions


Mythmaker

Senior Member
Had been reading around on full spectrum conversion (had no prior knowledge to this), but still have a few questions. Hopefully someone will be able to share his knowledge? :D

1) After conversion, I would still need filters to take pictures right? Hot Mirror (for normal colours) and IR (for IR) filters specifically. If I don't use any filters, the resulting image will be blurry?

2) I read around that using full spectrum + IR filter can result in handheld taken images, but cannot use the viewfinder. Are they referring to handholding with live view instead?

3) I understand that the UV filter will be removed, which will enable me to do astrophotography. What filter do I need in this case (for astrophotography)?

Thanks alot for helping!
 

I came across this article when I was researching on modding my camera for IR, I think it has some of the answers....
http://www.extremetech.com/electronics/144388-how-to-turn-your-dslr-into-a-full-spectrum-super-camera

1) After conversion, I would still need filters to take pictures right? Hot Mirror (for normal colours) and IR (for IR) filters specifically. If I don't use any filters, the resulting image will be blurry?
I had just removed the IR blocking filter from my EPL1, tested, image not blurry with or without IR filter in front.

2) I read around that using full spectrum + IR filter can result in handheld taken images, but cannot use the viewfinder. Are they referring to handholding with live view instead?
I took my test shots handheld, ISO 160. Without filter 1/1250 sec, 0 EV ; with filter 1/1000 sec, -0.7 EV.
 

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1) After conversion, I would still need filters to take pictures right? Hot Mirror (for normal colours) and IR (for IR) filters specifically. If I don't use any filters, the resulting image will be blurry?

From my experience, if you use live-view to focus, the image will still be sharp.
The resulting image will include visible light and infra-red, can still look quite nice sometimes. :)
If your image include include humans, sometimes you can get white foliage and still get quite nice skin tones under the right conditions.

2) I read around that using full spectrum + IR filter can result in handheld taken images, but cannot use the viewfinder. Are they referring to handholding with live view instead?
The reason is because our eyes are not sensitive to infra-red. So if you use viewfinder, you are viewing through the IR filter, so what you see will be very dark especially if you use IR filters that's 720nm and above. When you use the viewfinder, you are viewing with the help of the camera sensor which is sensitive to IR, so you can see and frame your image.

3) I understand that the UV filter will be removed, which will enable me to do astrophotography. What filter do I need in this case (for astrophotography)?
A lot of lenses by itself already block off UV. So even with the UV filter removed, a lot of UV will still be blocked.
So you need to find suitable lenses that do not block UV.
If you want to filter visible light and allow UV to pass through only, there are also filters available but very much more expensive compared to IR filter. (you still need to find suitable lenses that do not block UV though :) )
 

I came across this article when I was researching on modding my camera for IR, I think it has some of the answers....
http://www.extremetech.com/electronics/144388-how-to-turn-your-dslr-into-a-full-spectrum-super-camera


I had just removed the IR blocking filter from my EPL1, tested, image not blurry with or without IR filter in front.


I took my test shots handheld, ISO 160. Without filter 1/1250 sec, 0 EV ; with filter 1/1000 sec, -0.7 EV.

Thank you for your reply :)

Actually, I did came across that site. It answered a few questions, but gave a few more haha.

From my experience, if you use live-view to focus, the image will still be sharp.
The resulting image will include visible light and infra-red, can still look quite nice sometimes. :)
If your image include include humans, sometimes you can get white foliage and still get quite nice skin tones under the right conditions.


The reason is because our eyes are not sensitive to infra-red. So if you use viewfinder, you are viewing through the IR filter, so what you see will be very dark especially if you use IR filters that's 720nm and above. When you use the viewfinder, you are viewing with the help of the camera sensor which is sensitive to IR, so you can see and frame your image.


A lot of lenses by itself already block off UV. So even with the UV filter removed, a lot of UV will still be blocked.
So you need to find suitable lenses that do not block UV.
If you want to filter visible light and allow UV to pass through only, there are also filters available but very much more expensive compared to IR filter. (you still need to find suitable lenses that do not block UV though :) )

Thanks! I understand #1 and #3 much better le :D

For #2, my experience with IR filter (Kenko Pro1D R72) is machiam a 14 stop ND filter. Live view needs 30s (tripod needed), which is why I asked that question haha. So you mean once I go full spectrum, put on the Kenko Pro1D R72, I can easily shoot handheld? The shutter speed will be > 1/60?
 

For #2, my experience with IR filter (Kenko Pro1D R72) is machiam a 14 stop ND filter. Live view needs 30s (tripod needed), which is why I asked that question haha. So you mean once I go full spectrum, put on the Kenko Pro1D R72, I can easily shoot handheld? The shutter speed will be > 1/60?

Yes once you go full spectrum, you can use normal settings just like a normal camera (except the white balance). No longer need to long expose since the IR blocking filter is no longer there :)
 

Had been reading around on full spectrum conversion (had no prior knowledge to this), but still have a few questions. Hopefully someone will be able to share his knowledge? :D

1) After conversion, I would still need filters to take pictures right? Hot Mirror (for normal colours) and IR (for IR) filters specifically. If I don't use any filters, the resulting image will be blurry?

2) I read around that using full spectrum + IR filter can result in handheld taken images, but cannot use the viewfinder. Are they referring to handholding with live view instead?

3) I understand that the UV filter will be removed, which will enable me to do astrophotography. What filter do I need in this case (for astrophotography)?

Thanks alot for helping!

I have converted myself a Pen PL3 and a Point and shoot camera to full spectrum, means no IR filter place in front of image sensor and require external lense snap on filter.

To answer your questions:
1) If no IR filter put on a full spectrum camera, and the white balance been set to Auto-WB. For day time outdoor, all images will become red colour. For night time (no sun light) under fluorucent lamps, it is like normal camera because the surrounding IR are very weak or no IR at all.

2) If you use mirror-less IR converted cameras, the electrical viewfinder signal is same as the liveview from LCD. So there is no different. But for DSLR converted camera, you will have some problem in view through the optical viewfinder after the IR filter been put on.

3) U1 and U3 filters will be good for astrophotography.
 

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